Biomedical subjects

Paul Verhaeghen

Publications and source records attributed to Paul Verhaeghen.

15 recordsLinked to original sources

PubMed2007

Aging, focus switching, and task switching in a continuous calculation task: evidence toward a new working memory control process.

This study examined switching of the focus of attention in working memory in relation to global task switching in a continuous calculation task using two rules (midpoint and up-and-down) in a group of 25 younger adults and a group of 23 older adults. Age differences emerged in accuracy when participants worked on two strings simultaneously (necessitating a focus switch); focus switching did not interact with age in the response time domain. No age differences were obtained for global task switching. Ex-Gaussian decomposition showed a shift due to focus switching in all parameters, but a shift in leading edge only for task switching. The results suggest that task switching and focus switching rely on different processes, and that there is a specific age-related deficit in focus switching.

Adolescent↗

PubMed2006

Aging, task complexity, and efficiency modes: the influence of working memory involvement on age differences in response times for verbal and visuospatial tasks.

We examined the information-processing functions (response-time x load) of younger and older adults for two verbal and one visuo-spatial task; each task was implemented in a baseline and a high-complexity condition. Heightened complexity transformed the baseline functions in either an additive or a multiplicative fashion. The processing efficiency of older adults was defined as the old-young ratio of the slopes of the load functions. Three levels of efficiency could be distinguished. The first level, with an age-related slowing factor of about 1.2, consisted of low-complexity verbal processing and additive-complexity verbal processing. The second level, associated with a slowing factor of about 1.6, consisted of a mixture of verbal-high-multiplicative-complexity processing and visuo-spatial-low-complexity processing. The third level, with a slowing factor of about 4, consisted of visuo-spatial processing of high multiplicative complexity. The results go against any common factor theory of aging. Instead, they suggest that a shift from a higher to a lower mode of efficiency is triggered by a greater degree of working memory involvement.

Adolescent↗

PubMed2006

Verbal labeling as an assimilation mnemonic for abstract visual stimuli: the sample case of recognition memory for Chinese characters.

In four experiments, we examined the effect that presenting a verbal stimulus (viz., an English noun) alongside an abstract visual stimulus (viz., a Chinese character) enhances recognition memory for the abstract visual stimulus. Experiment 1 demonstrated that the character-plus-word combination at both encoding and retrieval results in better recognition than does a character-alone presentation or presenting the combination at encoding only. Experiment 2 demonstrated that presenting the word first and then the character results in better performance than does the opposite order. Experiment 3 showed that the concreteness value of the word, not familiarity, is the critical factor. In Experiment 4, presentation time was varied. More time was needed for liftoff from chance level for the word-character combination than for the character-alone presentation. Together, the results suggest that subjects spontaneously assimilate stimulus and word into a single representation by building asymmetric effortful imagery associations, going from the English word to the Chinese character.

China↗

PubMed2005

Why we sing the blues: the relation between self-reflective rumination, mood, and creativity.

Past research has shown that creative behavior is associated with a higher risk for depression. The authors hypothesized that a 3rd underlying factor, namely, self-reflective rumination, may explain the connection. This hypothesis was examined in a sample of 99 undergraduate college students, using path analysis. The authors found that self-reported past depressive symptomatology was linked to increased self-reflective rumination. Rumination, in turn, was related to current symptomatology and to self-rated creative interests and objectively measured creative fluency, originality, and elaboration. No direct link existed between currently depressed mood and either creative interest or creative behavior. These results suggest that the association between depression and creativity is solely the result of rumination.

Adult↗

PubMed2005

Ageing and switching of the focus of attention in working memory: results from a modified N-back task.

We conducted two experiments using a modified version of the N-Back task. For younger adults, there was an abrupt increase in reaction time of about 250 ms in passing from N = 1 to N > 1, indicating a cost associated with switching of the focus of attention within working memory. Response time costs remained constant over the range N = 2 to N = 5. Accuracy declined steadily over the full range of N (Experiment 1). Focus switch costs did not interact with either working memory updating (Experiment 1), or global task switching (Experiment 2). There were no age differences in RT costs once general slowing was taken into account, but there was a larger focus-switch-related accuracy cost in older adults than in younger adults. No age sensitivity was found for either updating or global task switching. The results suggest (a) that focus switching is a cognitive primitive, distinct from task switching and updating, and (b) that focus switching shows a specific age-related deficit in the accuracy domain.

Adolescent↗

PubMed2005

Aging and verbal memory span: a meta-analysis.

Using Brinley plots, this meta-analysis provides a quantitative examination of age differences in eight verbal span tasks. The main conclusions are these: (a) there are age differences in all verbal span tasks; (b) the data support the conclusion that working memory span is more age sensitive than short-term memory span; and (c) there is a linear relationship between span of younger adults and span of older adults. A linear model indicates the presence of three distinct functions, in increasing order of size of age effects: simple storage span; backward digit span; and working memory span.

Adult↗

PubMed2004

A working memory workout: how to expand the focus of serial attention from one to four items in 10 hours or less.

Five individuals participated in an extensive practice study (10 1-hr sessions, 11,000 trials total) on a self-paced identity-judgment (1)n-back task (n ranging from 1 to 5). Within Session 1, response time increased abruptly by about 300 ms in passing from n = 1 to n > 1, suggesting that the focus of attention can accommodate only a single item (H. Caravan, 1998; B. McElree, 2001). Within Session 10, response time was dramatically reduced and increased linearly with n for n < or = 4, with a slope of about 30 ms. The data suggest that working memory consists of a focus of attention governed by a limited-capacity search, expandable through practice, and a content-addressable region outside the focus of attention.

Attention↗

PubMed2004

Adult age and digit symbol substitution performance: a meta-analysis.

This article reports the results of a meta-analysis of the effects of age, education, and estimated year of measurement on scores from the Wechsler Adult Intelligence Scale and the Wechsler Adult Intelligence Scale-Revised Digit Symbol Substitution Test. Analysis of effect sizes for age reported in 141 studies published between 1986 and 2002 indicated a mean standardized difference of -2.07. Age accounted for 86% of the variance in a regression model using age, education, and year submitted as predictors of Digit Symbol scores. There was no association between years of education or year submitted and Digit Symbol scores for younger adults or older adults.

Adult↗

PubMed2003

Trait anger, anger expression, and ambulatory blood pressure: a meta-analytic review.

A meta-analysis of 15 studies was conducted to investigate the relationship between trait anger and ambulatory blood pressure. Overall, the experience of anger was significantly and positively associated with systolic blood pressure (r+ = 0.049), but not reliably associated with diastolic blood pressure (r+ = 0.028). After removing an outlier, the expression of anger was found to have a reliable inverse relationship with diastolic blood pressure (r+ = -0.072). No reliable relationship between expression of anger and systolic blood pressure (r+ = -0.041) was found. These results continue to support the modest role of self-reported trait anger and anger expression in blood pressure levels. Several suggestions for future research are discussed, including increasing the focus on the complexity and synergism of these effects.

Adult↗

PubMed2003

Subitizing speed, subitizing range, counting speed, the Stroop effect, and aging: capacity differences and speed equivalence.

Thirty younger and 29 older adults were tested on reaction times for set size of a display of 1 to 9 digits. On half of the trials, the nominal value of the digits was equal to the size of the set displayed; on the other half, the value differed by 1 from the set size (Stroop interference). We found evidence for age differences in subitizing span (2.83 vs. 2.07). Once individual differences in subitizing range were taken into account, no age differences were found in the rate of either subitizing or counting, and no individual differences were apparent in subitizing speed. There was no age difference in the susceptibility to the Stroop effect. The results suggest that, with advancing age, the size of the focus of attention may shrink, but speed of access to elements in the focus of attention may remain constant.

Adolescent↗

PubMed2003

The fate of cognition in very old age: six-year longitudinal findings in the Berlin Aging Study (BASE).

The authors report full-information longitudinal age gradients in 4 intellectual abilities on the basis of 6-year longitudinal changes in 132 individuals (mean age at T1 = 78.27, age range = 70-100) from the Berlin Aging Study. Relative to the cross-sectional parent sample (N = 516, mean age at T1 = 84.92 years), this sample was positively selected because of differential mortality and experimental attrition. Perceptual speed, memory, and fluency declined with age. In contrast, knowledge remained stable up to age 90, with evidence for decline thereafter. Age gradients were more negative in old old (n = 66, mean age at T1 = 83.04) than in old (n = 66, mean age at T1 = 73.77) participants. Rates of decline did not differ reliably between men and women or between participants with high versus low life-history status. They conclude that intellectual development after age 70 varies by distance to death, age, and intellectual ability domain.

Age Factors↗

PubMed2003

Aging and vocabulary scores: a meta-analysis.

Vocabulary scores were examined in a total of 210 articles, containing 324 independent pairings of younger and older adults, from the 1986-2001 issues of Psychology and Aging. The average effect size, favoring the old, was 0.80 SD. Production tests yielded smaller effects (0.68 SD) than multiple-choice tests (0.93 SD). Both age and education were found to be partially independent determinants of performance in production tests; age effects disappeared in multiple-choice tests as soon as education was taken into account. In addition, the Wechsler Adult Intelligence Scale--Revised Vocabulary subtest (D. Wechsler, 1981) was also found to be sensitive to the Flynn effect (J. R. Flynn, 1987; i.e., increasing test scores with advancing birth year). The results question the approach of using age-group equality in vocabulary scores as a check on sample equivalence.

Adolescent↗

PubMed2003

Aging and dual-task performance: a meta-analysis.

The relations between dual-task effects and aging were examined through a meta-analysis of 33 studies (with 48 independent participant groups) using latency as the dependent measure and 30 studies (with 40 independent participant groups) focusing on accuracy. Brinley plots and state traces were derived, and a model to explicate different types of complexity (additive and multiplicative) was developed. The effects of dual-task processing on latency were additive, and this additive cost was larger in older adults than in younger adults and larger than predicted from general slowing. This cost was small and independent of task complexity. The effects of dual-task processing on logit-transformed accuracy were likewise additive, but no specific age deficit was associated with this dual-task cost.

Adult↗

PubMed2002

Aging, executive control, and attention: a review of meta-analyses.

We review the results of a series of meta-analyses by the first author and colleagues, examining age-related differences in selective attention (Stroop-task survey and negative-priming task survey) and in divided attention (dual-task survey and task-switching survey). The four task families all lent themselves to state trace analysis, in which performance in baseline conditions was contrasted with performance in experimental conditions separately for college-aged subjects and for elderly subjects. These analyses found no age-related deficits specific to selective attention or local task-switching. Age deficits were found for dual-task performance and global task-switching. Unlike selective attention and local task-switching costs, dual-task and global task-switching costs were found to be additive in both young and old subjects, unmodulated by task difficulty. These forms of executive intervention then did not alter computational processes already present in the simple tasks, but rather added one or more additional processing steps or stages to the processing stream. The cost was greater in older adults, but was limited to those experimental conditions that activated multiple task sets.

Aging↗

PubMed2002

Cognitive efficiency modes in old age: performance on sequential and coordinative verbal and visuospatial tasks.

In an experiment using a large set of verbal and spatial tasks requiring low or high degrees of executive control, 3 distinct age-related effects were found. The smallest effect (no slowing) was tied to lexical tasks with low executive involvement, the largest deficit (age-related slowing factor of 2.2) was tied to visuospatial tasks with high executive involvement, an intermediate level of deficit (slowing factor of 1.7) was found for visuospatial tasks with low executive load and verbal tasks with high executive load. These age-related dissociations were incompatible with any "common cause" formulation. The mechanism responsible for the dissociation between verbal and visual tasks, and between low and high executive load remains to be determined. The latter may reflect capacity limits.

Adult↗